755 Storage Controller

765 Mushroom Controller

Air Liners for Mushrooms for Mushrooms

Impact Recording Device

Humidity Sensors

Fresh air intake door

In floor Air Cup System

Plenum fan installation







How do I ship potato samples to the laboratory for sugar and process quality analysis?

To schedule your samples for processing please call the laboratory manager at 517-322-0250.  The lab will schedule a day to receive your samples and ensure timely processing.  For more information about the laboratory program visit our lab page here.

How do I schedule a service call from a Techmark technician?

You should call Techmark to schedule service for your Fancom systems, 517-322-0250.  We will schedule the correct technician based on your system type.  For a general inquiry to help with trouble shooting you may also email us at

How do I calibrate my RH sensor on a 755 Controller?  Printable Version


  1. Remove the wick from the wet bulb and wait 30 minutes.  At this point both the dry and wet bulb should be seeing the same temperatures.  Make sure the RH fan is working and the door to the RH canister is closed.
  2. Determine the Dry and Wet Analog Input numbers in the SYSTEM menu of the 755.
    1. Press button 22 SYSTEM key - password is Button 10 and then EDIT or # Key.
    2. Press right arrow key when the cursor is flashing on INPUTS to access the INPUTS menu.
    3. Press the single down arrow key once.  The cursor will move to INSIDE CLIMATE
    4. Press right arrow key into INSIDE CLIMATE
    5. The display will read RH Plenum - Dry/Wet.  A number will display behind the RH-D and RH-W assignments on the second line.  Record values below.
        1. RH-D: __________     RH-W: __________  Bin 1
        2. RH-D: __________     RH-W: __________  Bin 2
        3. RH-D: __________     RH-W: __________  Bin 3
        4. RH-D: __________     RH-W: __________  Bin 4
  3. Adjust the sensor readings.
    1. Back out of the INSIDE CLIMATE menu by pressing the left arrow key once.  The display will return to the INPUTS menu.
    2. Press the single down arrow key 3 times.  The cursor will be flashing on 5 ANALOG MEAS.
    3. Press the right arrow key into ANALOG MEAS.  Note it will read ANALOG MEAS_1.  This means it is Analog Input 1.
    4. Press the double up arrow key until the RH-D measurement recorded above is displayed.
    5. Press the down arrow key twice.  The display will show the measured values of the RH-D sensor i.e. 221. Record the measured value here:________
    6. Press the double up arrow key to display the RH-W input recorded above. Record the measured value                     here: __________
    7. These two measured values should be equal.  If not, adjust the wet sensor by changing the value under the Zero setting.
      1. Press the down arrow key 3 times to see the Zero and Span lines.  Increase by 1 to increase the measured value by 1.  Do not change the Zero by more than 5 up(+) or down(-).  If an adjustment of +/- 5 is not sufficient the sensor or wire will need to be replaced.
    9. Record the new WET ZERO: __________ and RH-W measured value: __________
    10. Record the current RH-D measured value (press the double down arrow to view this): ________
    11. These two values should now match

How to calibrate an Inlet door on a 755 controller? Printable Version


  1. Close the door with the knob on the relay  panel.
  2. Press button 22 on the 755.  The display will ask for a password which is button 10.  Press the # button.
  3. Press the right arrow to go into INPUTS and then the single down arrow and go to ASSIGN MEAS.  Press the right arrow to go into this and then use the single down arrow to go to the bottom of the list to AIR INLET (make sure the correct bin light is on).  Not this number: ______
  4. Press the left arrow to go back to INPUTS and then the single down arrow and go to ANALOG MEAS.  Press the right arrow to go into this.  ANALOG INPUT 1 should be showing.
  5. Press the double up arrow to go to the ANALOG INPUT found.
  6. Press the single down arrow until the C in CALIBRATE U/R is blinking.
  7. Press the # key so that the 0 after CALIBRATE U/R is blinking.
  8. Press the single up arrow once and the ZERO should appear.  Press # and wait for the word ZERO to change back to 0.
  9. Open the door with the knob on the relay panel.  Wait until the door fully opens.
  10. Press the #.  Press the single up key until SPAN is showing.  Press # and wait until 0 shows.
  11. Close the door with the knob and wait until the door is completely closed.
  12. Press the single down arrow to get to the bottom of the screen where the words ZERO and SPAN are.
  13. Press the # key so the Z in zero is blinking.  Press the DOUBLE UP ARROW 4 to 5 times then press the # twice.
  14. Press the air inlet button.  The reading for MEAS should be 1. Put the knob in auto.

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